5. Configure sshd2 to use tcp-wrappers/inetd super server

Tcp-wrappers shoud be enabled to start and stop the sshd2 server. Upon execution, inetd reads its configuration information from a configuration file which, by default, is /etc/inetd.conf. There must be an entry for each field of the configuration file, with entries for each field separated by a tab or a space.

  1. Edit the inetd.conf file, vi /etc/inetd.conf and add the line:

             ssh	stream	tcp	nowait	root	/usr/sbin/tcpd	sshd -i


    The -i parameter is important since it specifies that sshd is being run from inetd. Also, update your inetd.conf file by sending a SIGHUP signal, killall -HUP inetd after adding the above line into the file.

    To update your inetd.conf file, use the following command:

             [root@deep] /#killall  -HUP inetd

  2. Edit the hosts.allow file, vi /etc/hosts.allow and add the line:

             sshd: win.openna.com

    Which means client with host name win.openna.com is allowed to ssh on the server.


    These daemon strings for tcp-wrappers are in use by sshd2:

    sshd, sshd2

    The name sshd2 was called with usually sshd.


    if you want to allow/deny X11-forwarding.


    for tcp-forwarding.


    port-name defined in /etc/services. Used in tcp-forwarding.


If you do decide to switch to using ssh, make sure you install and use it on all your servers. Having ten secure servers and one insecure is a waste of time.